The present disclosure is directed to the processing and collection of blood and its components. More particularly, the present disclosure is directed to a method of collecting whole blood in a suitable anticoagulant, holding the anticoagulated whole blood for a selected period of time, separating concentrated red blood cells from the previously held whole blood and storing the same.
This disclosure generally relates to a biological fluid processing system and method thereof. More specifically, this disclosure relates to a system and method for a therapeutic exchange procedure that exchanges at least one constituent component, such as a blood component, from a withdrawn biological fluid, such as whole blood, from a patient with one or more replacement fluids that are infused to the patient.
Blood processing systems and methods that relate to a therapeutic exchange procedure typically withdraw a biological fluid, such as whole blood, from a patient. The biological fluid, such as whole blood, may be directed to a separator, such as a centrifugal or membrane assembly, for separation of at least one constituent component, such as at least one blood component, for example, red blood cells, plasma and/or platelets, from the remaining blood components. Depending on the procedure, certain separated constituent components may be retained by the system and not returned to the patient. The remaining separated constituent components may be returned to the patient together with one or more fluids to replace the constituent retained by the system. The particular separated constituent that is not returned to the donor may depend on the specific medical needs of the patient. For example, one type of therapeutic exchange procedure is a red blood cell exchange procedure that removes a quantity of separated red blood cells from the withdrawn whole blood of a patient and returns to the patient at least one replacement fluid, such as red blood cells from a healthy donor, containing an additive solution or other fluid, along with the remaining separated blood components.
In a therapeutic exchange procedure, it is generally desired to achieve a certain target fraction of original patient cells remaining, FCR, in order to reduce the population of diseased cells. It is also desired to maintain a patient's fluid volume such that the difference between the volume of removed fluid and replaced fluid, ΔV, is within a desired range. In a red blood cell exchange procedure it may also be desired to achieve a targeted volume fraction of red blood cells (fractional hematocrit, HT) at the conclusion of the procedure so as to avoid the patient receiving too many or too few replacement red blood cells. A system and method for controlling hematocrit during a therapeutic red blood cell exchange procedure utilizing a hematocrit sensor is disclosed in US 2009/0211987, incorporated herein by reference.
By way of the present disclosure, systems and methods for achieving a target FCR, hematocrit, and fluid volume change during a therapeutic red blood cell exchange procedure are disclosed, as well as systems and methods for performing such a procedure with isovolemic (i.e., without any change in volume) hemodilution.